clark



3 sheets-sheen 1.

IU I mvEn' lllill Patented Jan. 5, 1897,

(NuModel.)

F. L. CLARK.

PUMP. No. 574,664.

(No Model.) s sheets-sheet 2.

F. L. CLARK.

PUMP. i No. 574,664. ZI Patented Jan. 5, 1897.'v

HI VH l taf WITNESISS:

(No Model.) 3 Sheets-Sheet 8.

l F. L. CLARK.

UNITED STATES PATENT OEEICE.

FRANCIS L. CLARK, OF STEIVART STATION, PENNSYLVANIA.

PUMP.

SPECIFICATIONforming part of Letters Patent No. 574,664, dated` January5, 1897.

Application filed February 17, 1896. Serial No. 579,512. (No model.)

To all whom, it 71mg concern:

Be it known that I, FRANCIS L. CLARK, a citizen ot' the United States,residing at Stewart Station, in the county of Westmoreland and State ofPennsylvania, have invented or discovered al certain new and usefulImprovement in Pumps, of which improvement the following is aspecification.

The object of my invention is to provide a simple, compact, and e'ectivedevice for forcing a liquid against pressure which shall be especiallyadapted to the requirements of a hydraulic-brake apparatus, as well asdesirably applicable in connection with hydraulic jacks and otherhydraulic-pressure devices in eftectin g compression to such degree asmay be required.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings, Figure 1 is a vertical longitudinalsection through a pump, illustrating an embodiment ofv my invention atthe line t t of Fig. 2; Fig. 2, a transverse section at the line of Fig.l; Fig. 3, a similar section at the line u o of Fig. 2 g Fig. 4, an endview in elevation of the valvecasing Fig. 5, a longitudinal centralsection through the same; Fig. 6, a vertical transverse section througha pump having supplemental pistons at the line y y of Fig. 8; Fig. 7, alongitudinal central section through the valve-casing of the same; Fig.8,' a vertical longitudinal section through the pump at the lines .e e'of Figs. 6 and 9, and Fig. 9 a transverse section at the line w w ofFig. 8.

In the practice of my inventionl provide a pump-supporting frame 10,adapted to be located in proper relation to an element for impartingpower, which in this instance is indicated as the tread of a car-wheel2, but which may without variation of operative principle be locatedupon any suitable shaft rotated either by hand or other motive power.The pump is of the two-cylinder single-acting type, and thepump-cylinders 4 4 are secured one opposite the other and in axial lineto a casing 9, which may be either formed integral with or connected tothe supporting-frame 10. A pump-shaft 23, which is iitted to rotate inbearings in the casin g 9,carries upon a squared portion of its lengthlocated between the side bars of the supporting-frame l0 a drivingroller24, the periphery of which projects beyond the frame l0 on one facethereof. Friction-rolls l2 are journaled on pins ll, iixed in the framelO nearits ends, their peripheries projecting beyond the frame similarlyto that of the drivin g-roller 24, so as to be rotated, as

is said roller, by frictional contact with the wheel 2, from which thedriving-power is imparted.

An eccentric 25 is vformed or tlxed upon the pump-shaft 23 at theportion thereof which is located between-the pump-cylinders 4 4, andVtwo eccentric strapsn 26 26 are tted around it, each strap beingprovided with a short arm or rod 27, which is coupled by a pin 28 to apiston 29, itting the adjacent pump cylinder 4. Each of theeccentricstraps 26 is cut away for the major portion of its width, so asthrough said portion to only surround about one-half of the periphery ofthe-eccentric. portion of the width of each eccentric-strap completelyencircles the eccentric, and the complete and cut-away portions arelocated at alternately opposite ends of the respective straps, as seenin Figs. 1 and 9. By this construction a large bearing-surface for theeccentric-straps is provided during the forcing strokes of the pistons,and the bearing of the rlhe remaining minor pistons on the eccentric ismade more nearly f central than would otherwise be the case. The end ofthe casing 9 farthest from the frame lO is closed by a screw-cap 30,which serves as an end bearing for the pump-shaft23- In order to obviatethe imposition of undue strain upon the pump, which might otherwise beoccasioned by the driving-roller 24 being held in contact with the wheelby which it is rotated with greater force than that necessary to insureefficient frictional contact, the casing 9 and its accessories may beconnected to the supporting-frame 10 through the intermediation of ayielding or elastic medium. As shown in Figs. l, 2, and 3, the casing 9is fitted in a transverse recess in the frame 10, with the capacity of alimited degree of traverse toward and from the periphery of the wheel 2,from which power is transmitted to the driving-roller 24, which is heldto its bearing against the wheel 2 by springs 40,

IOO

which abut against the casing i) and against a bearing-plate 4l, securedto the frame lO by bolts 42.

The outer ends of the pump-cylinders 4 4 are connected by pipes 5 5 withchambers 32 in a valve-casing 3l, which may be located and supported inany convenient position relatively to the pump. Openings or passages areformed in the upper and lower sides of the chambers S2, which openingsare controlled, respectively, by upwardly-opening delivery-valves 33 andreceiving-valves 34, and lead, respectively, to an upper outletchamber35 and to a lower inlet-chamber 3G. A receiving-pipe 5l leads from anysuitable source of Huid-supply into the inlet-chamber 3G and adelivery-pipe 5 leads from the outletchamber 35 to any desired point ofdelivery or discharge.

In operation the inward stroke of each of the pistons 20 draws liquidfrom the pipe 5c and inlet-chamber 3G into one of the chambers 32,raising the inlet-valve S4 and tending to close the outlet-valve 33thereof. The opposite or outward stroke of each piston forces liquidfrom one of the chambers into the outlet-chamber 35 and discharge-pipe5, raising the outlet-valve 33 of the chamber 32 andtendingtoclosetheinlet-valve34. Theliquid discharged from thevalve-casing through the pipe 5l may be conveyed to any desired point ofdelivery against pressure,or, in a hydraulicbrake apparatus or otherapparatus in which such traverse is desired, may be circulated through apipe system and returned to the valvecasin g through the pipe 5C. Theyielding resistance of the springs 4U maintains a normal degree offrictional contact between the driving-roller and the wheel by which itis rotated and prevents undue strain if the supporting-frame l0 shouldbe held too closely to the shaft of said wheel. The frame l0 mayobviously be either fixed to a suitable base or stand or connected bylinks or suspensionrods through openings 50 51, provided for thereception of connecting-bolts, or through one of the pins ll, to theframing of an apparatus in connection with which it is employed, as, forexample, a car frame or sill when used in a hydraulic-brake system, sothat by being moved toward or from the wheel which imparts rotation tothe driving-roller 24, and thereby bringing said members into and out offrictional contact, the pump may either be actuated or remain inactive,as required.

Figs. (5 to il, inclusive, illustrate a modification in which, by theemployment of a supplemental piston in each pump-cylinder, a largeamount of fiuid may be pumped at comparatively low pressure, andthereafter a smaller amount may be pumped at a substantially higherpressure. The pump-casing 9 is in this instance made integral with thesupporting-frame l0, and the pump-shaft 225 is journaled in bearings inthe casing and its cap 30, as in the former case. The drivingroller 24,friction-rolls l2, eccentric-25, straps 26, rods 27, valve-casing 31,and inlet and outlet valves and connecting-pipes are also allsubstantially similar to the corresponding members before described. Themain pistons 2S) are not, however, connected directly with the rods 27,as in the instance first described, but are actuated therefrom throughthe intermediation of supplemental pistons 44 of smaller diameter, whichwork in cylindrical chambers in the main pistons and are coupled to theeccentric-rods 7 by pins 2S. A peripheral flange or collar 4t, which isformed on the outer end of each of the supplemental pistons 44, engagesa corresponding shoulder in the inclosing chamber of the main piston2f), and thereby moves said piston with the supplemental piston 44during the inward traverse thereof. rlhe outward traverse of the mainpistons is effected by helical springs 48, which surround the mainpistons and bear at their outer ends on circumferential flanges thereon,from which sleeves 47, fitting enlarged bores in the pump-chambers 4,extend toward the shaft 23 and inclose the springs 48 for a portion oftheir length. The inner ends of the springs bear on the bottoms ofannular recesses 49 in the pump-chambers, said recesses and the sleeves47 serving as guides for the springs. The supplemental pistons areprovided with central extensions 45 of smaller diameter on their outerends, fitting corresponding bores in the outer end caps of the mainpistons.

In operation the inward strokes of the main pistons 29 draw liquid fromthe pipe 5C and their outer strokes discharge it through the pipe 5, asin the instance first described, the piston areas effective for thispurpose being those of the enlarged outer ends of the main pistons. Thenthe pressure against which the liquid is pumped becomes sufficientlygreat to overcome the tension of the springs 48, the latter arecompressed and their coils closed down upon one another by the mainpistons, which thereafter remain inactive at the limits of their innertraverse, and the further action of the pump is effected by the reducedpiston areas of the extensions 45 of the supplemental pistons, whichthen act to force a smaller quantity of liquid against a higherpressure. Upon a diminution of pressure be low that equal to the tensionof the springs the pump again operates on the liquid through the maximumpiston areas, fi. e., those of the outer ends of the main pistons.

I claim as my invention and desire to secure by Letters Patentm l. Thecombination, substantially as set forth, of a' frame adapted to besupported adjacent to a power-imparting shaft, a pumpcasing connected tosaid frame, a pum p-shaft journaled in said casing, pump-cylindersconnected to said casing, a frictional drivingroller and an eccentric,each fixed on the pump-shaft, pistons fitting the pump-cylin- IOO IIO

ders and coupled to straps on the eccentric, and friction-rollersjournaled in the frame with their axial planes parallel to that of thepump-shaft.

2. The combination, substantially as set forth, of a frame adapted to besupported adjacent to a power-imparting shaft, a pumpcasing fittingmovably in said frame, an elastic medium, as one or more springs,holding said casing to a bearing against the frame, a pump-shaftjournaled in said casing, pumpcylinders connected to said casing, africtional driving-roller and an eccentric, each fixed on thepump-shaft, and pistons fitting the pump-cylinders and coupled to strapson the eccentric.

3. The combination, substantially as set forth, of a pump-cylinder, amain and a supplemental piston, of larger and smaller diametersrespectively, tted to traverse therein, a spring for effecting thetraverse of the main piston in one direction, separable bearing-faces onthe main n and supplemental pistons, through which either coincidentmovement of both pistons may be effected, or inaction of the main pistonpermitted, and connections coupling the supplemental piston to arotatable shaft.

4. The combination, substantially as set forth, of a pump-cylinder, amain piston fitting therein, a supplemental piston of smaller diam eterfitted to traverse in the main piston,- a spring bearing longitudinallyon the main piston and on the pump-cylinder, a projection on thesupplemental piston adapted to abut, in one direction of its traverse,against the main piston, and connections coupling the supplementalpiston to a rotatable shaft.

5. The combination, substantially as set forth, of a pum p-cylinder, amain piston f1tting therein, a supplemental piston of smaller diameter,tted to traverse in and independently of the main piston, connectionscoupling the'supplemental piston to a rotatable shaft, a spring actingon the main piston and tending to effect its traverse in one directionindependently of the supplemental piston, and a projection on thesupplemental piston Which engages the main piston and eifects itstraverse in the opposite direction, When and only when it has been movedby the spring.

6. The combination, substantially as set forth, of a pump-cylinder, am'ain piston fitting therein, a supplemental piston of smaller diameterfitted to traverse inthe main piston,

a spring bearing longitudinally on the main piston and on thepump-cylinder, a projection on the supplemental piston traversing freelyin one direction in the main piston, a shoulder or bearing-face on themain piston against Which said projection abuts, in the oppositedirection, when and Whenever the main piston is brought into positiontherefor by the spring, and connections coupling the supplemental pistonto a rotatable shaft.

In testimony whereof l have hereunto set my hand.

FRANCIS L. CLARK.

Witnesses:

F. E. GAITHER, T. J. HOGAN.

